if your mobo uses intel matrix storage or nvidia media shield, the raid is hardware based.
windows provides built-in mirroring (raid-1), spanning (jbod), and striping (raid-0) using dynamic volumes, but the boot drive can't be striped. also, dynamic volumes will not perform as well a hardware raid array.
as for mobo-based raid, you can use a striped array as a boot device. but unless you're using old/cheap SSDs, you probably won't get much benefit from striping since most newer SSDs can already utilize 80% of the read bandwidth of many SATA controllers. and, you'll likely lose TRIM support (which is vital to keep SSDs at top performance) since the OS will communicating with the raid controller and not the SSDs.
if you're still determined to stripe your SSDs with your mobo raid, create the array first, then use cloning software to transfer the drive image from your existing boot device to the new array.
I currently have Win7 installed on a single WD VelociRaptor. I am planning on upgrading to 2 fast SSDs in software RAID 0 in the next month or two (probably by using my Motherboads RAID). I was hoping to avoid doing a fresh install, but am OK with doing it if necessary. Mostly, I just wanted to see if there was another way...
After I get the drives set up for windows7, can I simply:
1) clone the Raptor to the RAID 0 drive
2) shut down
3) unplug the Raptor (not necessary, but I would like to)
4) Change the boot options in BIOS
5) start up the PC
I have a feeling it wont be that easy because I know Win7 treats SSDs differently. I seem to recall needing to turn off Indexing...???

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